JP2009104911A - Plane lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a highly color-rendering desired emitted light color while avoiding generation of unintended interference fringes. <P>SOLUTION: A plane lighting system 10 includes a light guide plate 11 constituted by arraying "n" light guide blocks 21-28 obtained by cutting a transparent plate material of a predetermined thickness D at a predetermined pitch P and "n" LEDs 12-19 disposed at least on one end sides 35 of the "n" light guide blocks 21-28 opposite thereto. Arrayed boundary surfaces of the "n" light guide blocks 21-28 are mirror-finished. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a planar illumination device, and more particularly to an edge illumination type planar illumination device.

  As a prior art of the edge illumination type flat illumination device, for example, the one described in Patent Document 1 below is known. In this prior art, a straight light source (straight discharge tube such as a fluorescent tube) is arranged along an end surface (edge) of a light guide plate having a predetermined thickness, and light generated by the light source is transmitted from the edge of the light guide plate to the inside. Is applied to light the surface of the light guide plate, and a typical application is a back light source (backlight) of a liquid crystal display panel.

  On the other hand, the use of such an edge illumination type flat illumination device is expected to be used not only for the above backlight but also for signs, advertisements, etc. In addition, it is difficult to say that it is still widespread in general because of its large heat generation and the inability to obtain a free luminescent color rich in color rendering.

  From the viewpoint of life, power consumption and heat generation, a light emitting diode (hereinafter referred to as LED) may be used as the light source. This is because the LED has a longer life than a discharge tube such as a fluorescent lamp, and also consumes less power and generates less heat.

JP-A-6-314069

  However, even if the above prior art light source is replaced with an LED to achieve long life and power saving, unintentional interference fringes as described below may occur, or the color rendering properties may be rich. There is a problem that the emission color cannot be obtained.

  FIG. 17 is an inconvenience explanatory diagram of the prior art. In this figure, a plurality of LEDs 2 are arranged along an edge of the light guide plate 1 (hereinafter referred to as an end face, referred to as an upper end face in the figure). For convenience of explanation, assuming that the emission color of all LEDs 2 is pure white, this pure white light is also mixed light including the three primary colors of light (red, green, and blue). The irradiated light is guided to the inside of the light guide plate 1 at the edge surface (strictly, the boundary surface between the light guide plate 1 and air) at different refraction angles according to the respective color components (wavelengths thereof). Eventually, the light is guided into the light guide plate 1 as light having a certain spread.

  In the drawing, the “c” -shaped arrow lines 3 and 4 coming out of the respective LEDs 2 schematically represent the above “expansion”.

  The wavelength of red light is 625 to 740 nm, the wavelength of green light is 500 to 565 nm, and the wavelength of blue light is 450 to 485 nm. For this reason, one side (referred to as arrow line 3 for the sake of convenience) of the “C” -shaped arrow line in the figure is the direction of the short wavelength light (blue light) and the other side (for convenience, the arrow line). 4) is the direction of the long wavelength light (red light). Further, although not shown in the drawing, the direction near the middle of the “C” shape is the directivity direction of the medium wavelength light (green light). Then, since these light rays are repeatedly reflected and refracted inside the light guide plate 1, as a result, as shown by hatching in the figure, the light rays are mixed and an unintentional color pattern (interference fringes) is generated. .

  Further, if each of the plurality of LEDs 2 emits light of each of the three primary colors of light, that is, a red LED, a green LED, and a blue LED, and the emission ratio of these LEDs is appropriately controlled, a desired emission color can be obtained. Although an unintentional color pattern (interference fringes) is generated in the same manner due to the above-mentioned “mixing of light rays”, it is still impossible to obtain a uniform light emission color in the entire light guide plate 1 and color rendering. It is not possible to obtain a rich and flexible emission color.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a flat illumination device capable of obtaining a desired light emission color rich in color rendering properties while avoiding unintentional interference fringes.

The invention described in claim 1 includes a light guide plate configured by arranging n light guide blocks obtained by cutting a transparent plate-shaped material having a predetermined thickness at a predetermined pitch, and the n light guide blocks. A flat illumination device comprising: n LEDs arranged to face each other at least on one end side.
The invention according to claim 2 is the flat illumination device according to claim 1, wherein an array boundary surface of the n light guide blocks is mirror-finished.
According to a third aspect of the present invention, there is provided a light guide plate configured by arranging n light guide blocks obtained by cutting a transparent plate-shaped material having a predetermined thickness at a predetermined pitch, and the n light guide blocks. A light source unit including at least one LED disposed opposite to at least one end side; and a control unit that individually controls an operation mode of the n LEDs. The control unit designates an LED to be controlled. Specific information to control and control information indicating the operation mode of the control target LED is output to the light source unit via the bus line, and the light source unit selects the control target LED based on the specific information from the control unit. In particular, the flat illumination device is characterized in that the operation mode of the LED is changed based on control information from the control unit.

  In the present invention, the light guide plate is divided into n light guide blocks, and LEDs are arranged on the end faces of the respective light guide blocks. Preferably, the arrangement boundary of each light guide block is mirror-finished. Therefore, there is no leakage of light rays to adjacent light guide blocks, mixing of light beams having different wavelengths can be prevented, and generation of unintentional interference fringes can be avoided. In addition, by avoiding the generation of the interference fringes, a desired light emission color with rich color rendering can be obtained.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1A is a simplified external view of a flat illumination device according to an embodiment. In this figure, a flat illumination device 10 includes a light guide plate 11 having an upper surface (up, down, left and right are directions when facing the drawing; the same applies hereinafter) and one end surface (or both ends) of the light guide plate 11. And a light source group 20 including LEDs 12 to 19 (n is a number of 1 or more, and here, n = 8 for convenience, the same applies hereinafter) arranged along a plane. .

  The light guide plate 11 cuts a transparent plate-shaped material (preferably a plate-shaped resin material such as an acrylic plate) having a predetermined thickness D into a predetermined pitch P (for example, a strip shape) by, for example, laser processing. The n light guide blocks 21 to 28 are arranged, and n LEDs 12 to 19 are arranged on one end side (or both end sides) of each light guide block 21 to 28. Are arranged opposite to each other.

  FIG.1 (b) is a figure which shows the arrangement | positioning relationship between one light guide block and one LED. In this figure, n light guide blocks 21 to 28 have the same configuration (shape), and n LEDs 12 to 19 have the same configuration. As an example, the LED 12 includes a red LED element (hereinafter referred to as an R element) 29, a green LED element (hereinafter referred to as a G element) 30, and a blue LED element (hereinafter referred to as a B element) 31. Is a so-called “3 in 1 type”, and the light beam (R light beam 32, G light beam 33 and B light beam 34) from each of the R element 29, the G element 30 and the B element 31 is guided to the light guide block 21. Irradiate the end face 35 of the lens in parallel.

  The light guide block 21 includes the end face 35 irradiated with the R light 32, the G light 33, and the B light 34, the side surfaces 36 and 37 that are also cut by the laser processing, and the light emission of the flat illumination device 10. A columnar body having a rectangular cross section is formed by an upper surface 38 that is also a surface and a bottom surface 39 that is also the opposite surface of the upper surface 38. The upper surface 38 is preferably subjected to roughening processing for promoting irregular reflection of light, and the bottom surface 39 is a reflecting plate for preventing leakage of light to the outside or the equivalent. It is desirable that mirror film processing is performed. A thick line on the bottom surface 39 schematically represents a reflector or a processed portion.

  Now, the end surface 35 and both side surfaces 36 and 37 of the light guide block 21 need to be smooth and flat. This is because the R ray 32, the G ray 33, and the B ray 34 need to be guided into the light guide block 21 with low loss at the end face 35, and at the side faces 36, 37. The G light beam 33 and the B light beam 34 guided to the inside of the light guide block 21 need to be “totally reflected” by the side surfaces 36 and 37 (they need not be leaked to the adjacent light guide block). Because.

Here, the principle of refraction of light including total reflection will be described.
2 and 3 are diagrams showing Snell's law. As shown in FIG. 2, Snell's law means that when a light beam 5 passes through a boundary surface between different types of media (medium 1 and medium 2), refraction (n1 sin θ1 = n2sin θ2). As shown in FIG. 3A, the incident angle θ1 of the light beam 5 when the reflection angle θ2 is 90 degrees is particularly referred to as a “critical angle θ”. For example, the medium 1 is acrylic having a refractive index of 1.5, When the medium 2 is air having a refractive index of 1, 41.81 degrees can be obtained as the critical angle θ according to Snell's law. As shown in FIG. 3B, when the incident angle θ 1 of the light beam 5 is larger than the critical angle θ, the incident light beam 5 is not refracted into the medium 2, and “total reflection is performed at the boundary surface between the medium 1 and the medium 2. "

  FIG. 4 is a diagram illustrating a state of light refraction in the light guide block. In this figure, the light beams (the R light beam 32, the G light beam 33, and the B light beam 34) emitted from the n LEDs 12 to 19 have different refraction angles according to the respective color components (wavelengths thereof) and the light guide blocks 21 to 21. 28 is led to the inside. For example, the light guide block 21 at the left end will be described as a representative. An R light (long wavelength light) 32, a G light (medium wavelength light) 33, and a B light (short light) included in the light emitted from the LED 12. In other words, the light from the long wavelength to the short wavelength is led into the light guide blocks 21 to 28 with a certain spread.

  Here, since both side surfaces of the light guide block 12 (see reference numerals 36 and 37 in FIG. 1) are smooth and flat as described above, the R ray 32, the G ray 33, and the B ray 34 are These both end faces are “totally reflected” and do not leak into the adjacent light guide block 13. Incidentally, a virtual line 40 indicated by a broken line in the drawing schematically shows a leaked light ray when “total reflection” is not performed.

  In this way, the light beam propagated inside one light guide block 12 is irregularly reflected on almost the entire top surface (see reference numeral 38 in FIG. 1) of the light guide block 12 which has been roughened. Since the upper surface emits light with a uniform amount of light, the flat illumination device 10 can be used as an edge-type flat illumination panel.

  In addition, in the flat illumination device 10 of the present embodiment, the light beams propagating through the adjacent light guide blocks (for example, the light guide block 12 and the light guide block 13) do not leak beyond the block boundaries. The above-mentioned stripe pattern (interference fringe) is not generated, and good color development can be maintained.

  This is the same even when the LEDs 12 to 19 in FIG. 4 are not the “3 in 1” type, that is, any single emission color type. For example, even when the LED 12 is red, the LED 13 is green, the LED 14 is blue,..., The red light of the LED 12 irradiated to the light guide block 21 does not leak into the adjacent light guide block 22. Further, the green light of the LED 13 irradiated to the light guide block 22 does not leak to the adjacent light guide blocks 21 and 23, and the blue light of the LED 14 irradiated to the light guide block 23 is also adjacent to the light guide block 22. , 24 does not leak out.

  In the above embodiment, one LED is arranged for one light guide block, but the present invention is not limited to this. A plurality of LEDs may be arranged.

  FIG. 5 is a diagram illustrating an example in which a plurality of (here, three for convenience) LEDs are arranged for one light guide block. In this figure, each of the light guide blocks 21 and 22 shown as representative has three LEDs (LEDs 12 to 14 in the light guide block 21 and LEDs 15 to 17 in the light guide block 22). Has been placed. In this way, it is possible to increase the amount of light per light guide block. However, in this configuration, the width L of the light guide block should be as small (narrow) as possible. This is because there is a concern about interference fringes when the width L is large (wide).

  By configuring as described above, it is possible to realize the flat illumination device 10 that can easily obtain a desired light emission color rich in color rendering while avoiding the generation of unintentional interference fringes. In order to obtain a desired desired luminescent color, not only the structure of the light guide plate 11 of the flat illumination device 10 and the arrangement of the LED group 20, but also a method for controlling the respective LEDs 12 to 19 is required.

Hereinafter, this point will be described.
FIG. 6 is a block diagram of the entire system of the flat illumination device 10. In this figure, a power supply unit 41 converts commercial power into a required DC voltage and supplies it to a main controller 42. The main controller 42 has a plurality of light guide blocks 43 to 52 (in accordance with preset lighting pattern information). The lighting colors of the light guide blocks 21 to 28 in FIG. 1 are individually controlled.

  Here, each of the light guide blocks 43 to 52 is provided with a pair of light source units 57 including a drive unit 53 and LED elements (R element 54, G element 55, and B element 56) of the three primary colors of light. The R element 54, the G element 55, and the B element 56 correspond to the R element 29, the G element 30, and the B element 31 in FIG.

  As described above, the disadvantage of providing the light source unit 57 in pairs with each of the light guide blocks 43 to 52 is that the number of lines between the main controller 42 and each light source unit 57 is increased. . For example, in the example shown in the figure, two control lines for one light source unit 57 (three control signals are necessary because of the control of three RGB LEDs, and therefore two control lines are required. In other words, the number of the light sources 57 is only 10 in this figure, but eventually 2 × 10 + 1. There is a disadvantage that as many as 21 lines are required.

  The actual number of light source units 57 is much larger than the 10 illustrated above, and in some cases, it is several hundreds or more, so the actual number of lines is more than the above 21. There will be much more. As a result, a lot of space is allocated to accommodate a large amount of lines, which not only causes inconvenience in the system layout, but also causes problems such as manufacturing difficulties and inevitable cost increases.

  Therefore, in the present embodiment, the following measures are taken in order to avoid the above-described line number problem.

  That is, in FIG. 6, a common power supply line 58 is laid between the main controller 42 and each light source unit 57, and a common bus line 59 for transmitting control signals between the main controller 42 and each light source unit 57. Was laid. The bus line is a signal line for transmitting a multi-bit signal.

  FIG. 7 is an example format diagram of a transmission signal of the bus line 59. In this figure, the transmission signal 60 includes an ID part 61 and a light emission color information part 62, and the light emission color information part 62 includes an R information part 63, a G information part 64, and a B information part 65. Note that this format is merely an example that can be realized, and the outer edge of the technical idea of the present invention should not be specified with this example. In short, it is only necessary to have an information storage unit corresponding to the ID unit 61 and the emission color information unit 62, and the size, position, etc. of these storage units are not limited to those illustrated, and various modifications are possible. Of course it is possible.

  The main controller 42 individually controls the lighting colors of the light guide blocks 43 to 52 by storing necessary information in each part of the transmission signal 60 and outputting the information to each light source part 57.

  The ID part 61 of the transmission signal 60 stores unique information (hereinafter referred to as ID) for identifying each light source part 57. This ID is set individually for each light source unit 57 (the driving unit 53), and each light source unit 57 stores the same ID set in its own driving unit 53 in the ID unit 61. When the transmission signal 60 is received, the transmission signal 60 is determined to be the transmission signal 60 for itself, and the emission color information (the R information unit 63, the G information unit 64, and the transmission information 60 stored in the emission color information unit 62 of the transmission signal 60) Information stored in the B information section 65), and drives its three LED elements (R element 54, G element 55 and B element 56) according to the information.

  FIG. 8 is a principal block diagram of the flat illumination device 10. In this figure, a main controller 42 includes a voltage regulator 66 (“REGULATOR” in the figure) 66 for stabilizing a DC voltage from a power supply unit (not shown) (see the power supply unit 41 in FIG. 6), and a control constituted by a microcomputer. Each light source unit 57 stabilizes a DC voltage from a power supply unit (not shown) (see the power supply unit 41 in FIG. 6) supplied via the main controller 42 via the power supply line 58. In accordance with the voltage regulator 68 and the transmission signal 60 transmitted from the main controller 42 via the bus line 59, it is determined whether or not the transmission signal 60 is transmitted to the self by the ID matching determination. Is determined, the emission color information (R information unit 63, G information unit 64, and B information stored in the emission color information unit 62 of the transmission signal 60). Information stored in the unit 65) and driving the lighting of the three LED elements (R element 54, G element 55 and B element 56) according to the information, and the driving unit 53 individually The R element 54, the G element 55, and the B element 56 are driven to be lit or driven to increase / decrease the amount of the lit light.

  In the illustrated example, each of the R element 54, the G element 55, and the B element 56 is formed by connecting three LED elements in series (series), but is not limited thereto. One, two, three or more may be used, or a parallel connection may be used. The transistors 69 to 71 inserted between the R element 54, the G element 55, and the B element 56 and the ground are connected to the R element 54, the G element 55, and the B element 56 according to the output voltage of the driving unit 53. Resistive elements 72 to 74 that are active elements for interrupting or controlling increase / decrease of a current flowing to the ground, and inserted between the drive unit 53 and the base electrodes of the transistors 69 to 71. Is a bias resistance of the transistors 69 to 71, and the resistance elements 75 to 77 inserted between the R element 54, the G element 55, and the B element 56 and the collector electrodes of the transistors 69 to 71 are current limiting. Resistance.

  FIG. 9 is a diagram showing a simplified operation flow of each light source unit 57. In this flow, first, for example, the light source unit 57 in which “1” is set as the self ID includes the same ID (“1”) in the transmission signal 60 transmitted from the main controller 42 via the bus line 59. It is determined whether or not (step S1). If it is not included, step S1 is repeated. If it is included, it is determined that it is a transmission signal 60 for itself, and the emission color information (R information unit 63, G information unit) in the transmission signal 60 is determined. 64 and the information stored in the B information section 65 (step S2), and after driving the three LED elements (R element 54, G element 55 and B element 56) according to the information (step S3) Again, step S1 and subsequent steps are repeated.

  In this way, it is only necessary to lay one power line 58 and one bus line 59 between the main controller 42 and each light source unit 57, and the required number of lines regardless of the number of light source units 57. The signal line problem can be solved and problems such as system layout and cost increase can be solved.

  As described above, according to the present embodiment, it is possible to provide the flat illumination device 10 that can obtain a desired emission color rich in color rendering while avoiding the generation of unintentional interference fringes, Furthermore, a special effect can be obtained that the required number of lines between the main controller 42 and each light source unit 57 can be greatly reduced to eliminate problems such as system layout and cost increase.

  In addition, if the area of the light guide block with respect to the number of LEDs is reduced, the light emission amount of the light guide plate can be increased. By the way, in order to make the light reach far away, it is better to devise the shape of the light guide block and make the direction of light narrower and longer, or arrange the LED on the opposite side of the side where the LED is arranged In addition, lighting both LEDs together is one method for increasing the amount of light.

  In addition to arranging light guide blocks horizontally, a plurality of products arranged vertically and horizontally, or even three-dimensionally, can produce a more complex product with a high color rendering effect.

  FIG. 10 is an external view when a plurality of light guide blocks are arranged vertically and horizontally. In this figure, the flat illumination device 100 includes a light guide plate 101 having an upper surface as a light emitting surface, and a plurality of LEDs 102 to 109 arranged along two adjacent sides of the light guide plate 101.

  The light guide plate 101 is made of a plurality of transparent plate-like materials (preferably plate-like resin materials such as acrylic plates) having a predetermined thickness D cut into a rectangular shape at a predetermined pitch P in the vertical and horizontal directions, for example, by laser processing or the like. (In the example shown, for convenience, 4 × 4 = 12) light guide blocks 110 to 125 are arranged. Of the light guide blocks 110 to 125, the light guide plate 101 Each of the LEDs 102 to 109 is disposed on the exposed side surfaces of the light guide blocks 110, 114, 118, 122, 123, 124, and 125 located on two adjacent sides (here, seven).

  In the illustrated example, the vertical and horizontal cut dimensions (pitch) of each of the light guide blocks 110 to 125 are set to the same value (P), but this means that the cut shape of the light guide block is “square”. This is merely an example of the case, and for example, the vertical and horizontal cutting dimensions may be varied. That is, it is only necessary that the cut shape of the light guide block is a “rectangular shape” including a “square shape”.

  FIG. 11 is a plan view when a plurality of light guide blocks are arranged vertically and horizontally. In this figure, if the arrangement of the LEDs 102 to 105 is the X axis and the arrangement of the LEDs 106 to 109 is the Y axis, the light emitted from any pair of LEDs on each axis (for example, the LED 103 and the LED 107 painted black) The light guide blocks 114 and 123 in which the LEDs 103 and 107 are disposed are guided, and then the light guide blocks 114, 115 and 116 on the X axis and the Y axis adjacent to the light guide blocks 114 and 123. 117 and 123, 119, 115, and 111 are sequentially guided.

  Therefore, for example, if the color of light emitted from the LED 103 on the X axis is A and the color of light emitted from the LED 107 on the Y axis is B, the irradiation light of the LED 103 and the irradiation light of the LED 107 intersect. The light emission color of the light guide block 115 changes to a mixed color of A and B (C color).

   FIG. 12 is a diagram showing an example of a light emission pattern when a plurality of light guide blocks are arranged vertically and horizontally. Specifically, the X-axis light is moved in the X-axis direction and the Y-axis light is moved in the Y-axis direction. It is a figure which shows the example of the light emission pattern at the time of making it do. In this light emission pattern example, A color moves to the right in the drawing, B color appears to move downward in the drawing, and C color appears to move obliquely downward to the right. It is possible to bring about a visual effect as if the entire color of the light guide plate 101 moves obliquely. By applying this, it is possible to create an effect that the color pattern is rotating.

  In the above description, the light guide blocks are planar array (two-dimensional array), but the present invention is not limited to this, and for example, a stacked array (three-dimensional array) may be used.

  FIGS. 13A and 13B are diagrams showing an example of a laminated arrangement of light guide blocks, where FIG. 13A is an external perspective view, FIG. 13B is a side view, and FIG. 13C is a top view. In these drawings, the flat illumination device 200 includes a main light plate 201 having an upper surface as a light emitting surface, a sub light guide plate 202 stacked on the main light plate 201, and the main light plate 201 and the sub light guide plate 202. And a plurality of LEDs 203 to 209 arranged along one side surface.

  Although not shown, the main light guide plate 201 is made of a transparent plate-like material (preferably a plate-like resin material such as an acrylic plate) having a predetermined thickness, as in the above-described embodiment (see FIG. 1). For example, n light guide blocks (see light guide blocks 21 to 28 in FIG. 1) that are cut into a predetermined pitch (for example, a strip shape) by laser processing or the like are arranged and configured. The LEDs 203 to 207 are arranged to face each other on one end side of the light block.

  In this figure, the sub light guide plate 202 is composed of two light guide blocks 202a and 202b. The two light guide blocks 202a and 202b are arranged in a T-shape on the main light guide plate 201, and the light guides are respectively provided. The LEDs 208 and 209 are arranged to face each other on one end side of the blocks 202a and 202b. Here, the width (cutting pitch) of the light guide blocks 202a and 202b constituting the sub light guide plate 202 is equal to the width (cutting pitch) of a light guide block (not shown) constituting the main light guide plate 201, and the sub light guide plate. The light guide blocks 202a and 202b constituting 202 are positioned in a one-to-one relationship directly above a light guide block (not shown) constituting the main light guide plate 201.

  With such a stacked arrangement (three-dimensional arrangement), it is possible to create a visual effect as if the color is moving three-dimensionally.

  In addition, it is necessary to divide the light guide plate into blocks when making a product. However, since the side surfaces of the blocks use total reflection of light, it is necessary to perform precise processing so as to be as mirror-like as possible. For this purpose, after cutting with a laser or a saw, the cut surface should be polished in some cases.

In addition, examples of color rendering patterns that can be realized by the present embodiment include the following.
FIG. 14 is a diagram illustrating a first example of a color rendering pattern. In this figure, each vertical cell represents a light guide block. By setting each block to a different color and moving them gradually to adjacent blocks, it is possible to produce a color rendering effect as if the color moved between the blocks. For example, in the example shown in the figure, in the first stage, “red”, “orange”, “yellow”, “green”, “blue” are arranged in order from the left. Will shift to "White", "Red", "Orange", "Yellow", "Green". In the next stage, it will be shifted by one more to "Purple", "White", "Red", "Orange" ”And“ yellow ”, a color rendering effect is obtained in which the stripe pattern of these colors is sequentially shifted to the right.

  FIG. 15 is a diagram illustrating a second example of the color rendering pattern. Also in this figure, each of the vertically long cells is a light guide block. For example, “red 0, green 5, blue 95” written in each block indicates the light quantity ratio of RGB. In this case, “red = 0%”, “green = 5%”, “blue” = 95% ". By repeating the change of the light amount ratio for each block as shown in the figure, a color rendering effect as if it is rippled is obtained. For example, it is possible to create an animated image in which colors ripple by changing the light quantity ratio of each RGB to adjacent blocks several times or several tens of times per second.

  The above is an example of a color rendering pattern, but more effective color rendering can be performed by devising color change timing and hue. For example, if the primary colors of RGB are arranged at equal intervals, the remaining color (background color) is white, and the position of the primary color is moved for each display cycle, the primary color movement effect can be obtained. it can. Or, in addition to this, if the color of several lines following the primary color line is made to gradually fade from the primary color, the afterimage effect of the primary color (the effect of color movement with a trajectory) can be obtained. It is done. Alternatively, if the color between the primary colors is gradually changed (gradation), the effect of color movement accompanied by a trajectory using many intermediate colors can be obtained.

  In the above description, “strip shape” is cited as the cutting pattern of the light guide plate block, but this is only an example. For example, the following shapes may be used.

  16A and 16B are diagrams showing another example of the cutting pattern of the light guide plate block. FIG. 16A is an example of the cylindrical light guide blocks 301 to 308, and FIG. 16B is an example of the kamaboko light guide blocks 401 to 408. It is an example. In any example, LEDs 309 to 316 and 409 to 416 are arranged opposite to each other on one end surface of each block. The idea of the present invention includes at least the above-described strip shape and the illustrated cylindrical shape and kamaboko shape, and further includes other shapes not shown.

(A) is a simplified external view of the flat illumination device according to the embodiment, (b) is a diagram showing the arrangement relationship between one light guide block and one LED. It is a figure which shows Snell's law. It is a figure which shows Snell's law. It is a figure which shows the mode of the light refraction in a light guide block. It is a figure which shows the example at the time of arrange | positioning several (here 3) LED about one light guide block. 1 is a block diagram of an overall system of a flat illumination device 10. FIG. It is an example format figure of the transmission signal of the bus line 59. FIG. 2 is a block diagram of the main part of the flat illumination device 10. FIG. FIG. 6 is a diagram showing a simplified operation flow of each light source unit 57. It is an external view at the time of arranging a plurality of light guide blocks vertically and horizontally. It is a top view at the time of arranging a plurality of light guide blocks vertically and horizontally. It is a figure which shows the example of a light emission pattern at the time of arranging a plurality of light guide blocks vertically and horizontally. It is a figure which shows the laminated array example of a light guide block. It is a figure which shows the 1st example of a color rendering pattern. It is a figure which shows the 2nd example of a color rendering pattern. It is a figure which shows the other example of the cutting pattern of a light-guide plate block. It is inconvenient explanatory drawing of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Planar illumination apparatus 11 Light guide plate 12-19 LED
21-28 Light guide block 29 Bus line 42 Main controller (control part)
57 light source unit 100 flat illumination device 101 light guide plate 102 to 109 LED
200 Planar illumination device 201 Main light guide plate (light guide plate)
202 Sub light guide plate (light guide plate)
202a, 202b Light guide block 203-209 LED
301-308 Light guide block 309-316 LED
401-408 Light guide block 409-416 LED

Claims (3)

A light guide plate configured by arranging n light guide blocks obtained by cutting a transparent plate-shaped material having a predetermined thickness at a predetermined pitch;
A planar illumination device comprising: n LEDs arranged to face each other at least on one end side of the n light guide blocks.   2. The flat illumination device according to claim 1, wherein an array boundary surface of the n light guide blocks is mirror-finished. A light guide plate configured by arranging n light guide blocks obtained by cutting a transparent plate-shaped material having a predetermined thickness at a predetermined pitch;
A light source unit including n LEDs disposed to face at least one end of each of the n light guide blocks;
A control unit for individually controlling the operation mode of the n LEDs,
The control unit outputs unique information for designating a control target LED and control information indicating an operation mode of the control target LED to the light source unit via a bus line,
The said light source part specifies control object LED based on the specific information from a control part, and changes the operation | movement aspect of the LED based on the control information from a control part. The flat illuminating device characterized by the above-mentioned.

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